An alarm watch of this type is disclosed by Swiss Pat. No. 526,154 which shows a watch having a mechanism for activating an electrical contact. One of the members of this electrical contact is a projection on a metal arm formed integrally with a sleeve which is engaged as a force fit on the pipe of the hour cannon wheel of the watch. The other contact member is carried by an electrically insulating wheel which is coaxial with the time-indicating hands. A spring urges said insulating wheel against said projection on the said metal arm. This known construction is difficult to assemble.